Biochemistry, Biophysics, and Structural Biology Commons^™

Under Ice Photosynthetic Primary Production And Dark Carbon Fixation In A Temperate Freshwater System, Vanessa Cubillos Tellez

Dissertations, Master's Theses and Master's Reports

Ice-covered lakes are vulnerable to environmental change, especially those in the Northern Hemisphere where ice cover is rapidly declining due to global warming. These changes can alter metabolic processes and disrupt carbon cycling driven by primary producers who form the base of the food chain and are key to sustaining ecosystem function. Photosynthetic primary production and dark carbon fixation under the ice in the Keweenaw Waterway, a temperate freshwater system that is ice-covered for ~3 months out of the year, were studied using a carbon isotopic labeling (14C-bicarbonate) technique. Water samples were collected weekly during ice cover and monthly during …

Generation Of Chimeric Rhinoviruses Presenting Sars-Cov-2 Broadly Neutralizing Epitopes And Their Antigenicity Characterization, Danish Ansari

Biotechnology Theses

The global COVID pandemic is not yet fully under control as there were over 21 million new cases of SARS-CoV-2 infections and over 50,000 deaths globally as of January of 2022. A heavily mutated variant of concern, Omicron is responsible for most of these cases which demands an urgency for a new vaccine. NIH reports over 180 vaccine candidates that use various strategies currently in development. However, a recurring concern with these vaccines is that the continuous viral mutations decrease the efficacy of vaccines. Therefore, we proposed to construct a human rhinovirus (HRV) based chimeric virus containing highly conserved, broadly …

Development Of Novel Cellular Assay Model And Therapeutic Deep Eutectic Solvents To Optimize The Activity Of Anticancer Agents, Nizam Uddin

Electronic Theses and Dissertations

Multidrug resistance (MDR) is the major burden behind chemotherapeutic treatment failure. It is the principal mechanism by which cancer cells evade chemotherapeutic treatment. As a result, aggressive cancer cells survive and continue uncontrolled cell division. Multidrug resistance affects survival rate of almost all types of cancer patients and death toll rises at an alarming rate. There are seven different mechanisms for evolving MDR. The most common mechanism in efflux activity of overexpressed ABC transporters. MRP1 is a prominent ABC transporter that pumps out a wide variety of anticancer drugs from the cells and thereby reduces intracellular drug concentrations and develops …

Modulatory Effects Of Deacetylated Sialic Acids On Breast Cancer Resistance Protein-Mediated Multidrug Resistance And Receptor Tyrosine Kinase-Targeted Therapy, Isaac Tuffour

Electronic Theses and Dissertations

Multidrug resistance (MDR) remains a major challenge in cancer treatment, accounting for over 90% of chemotherapeutic failures. Cancers utilize sugar residues to engage in multidrug resistance. The underlying mechanism of action involving glycans, specifically the glycan sialic acid (Sia) and its various functional group alterations, has not been explored. ATP-binding cassette (ABC) transporter proteins, key proteins utilized by cancers to engage in MDR pathways, contain Sias in their extracellular domains. Modulating the expression of acetylated-Sias on Breast Cancer Resistance Protein (BCRP), a significant ABC transporter implicated in MDR, in lung and colon cancer cells directly impacted the ability of cancer …

Reconstructing The Germination Pathway From The Rafflesia Seed Transcriptome, Venkata Siva Sankar Maddu

Selected Full-Text Master Theses 2021-

Rafflesia (Rafflesiaceae) produces the largest flowers in the world but has no stems, roots, or leaves. It is a holoparasitic angiosperm that derives all its nutrients from its host vine, Tetrastigma. All species are also threatened with extinction, but propagating it has been incredibly challenging. Its germination from seed has never been observed. The thesis aims to reconstruct the germination pathway of Rafflesia from its published seed transcriptome to gain insight into its molecular genetics and understand what germination genes can be stimulated to facilitate infection of its host for ex-situ propagation. The published seed transcriptome of Rafflesia speciosa was …

Lipid Binding Properties Of Huntingtin As A Novel Therapeutic Target, Chathuranga Siriwardhana

Graduate Theses, Dissertations, and Problem Reports (ETD)

As protein aggregation is the defining hallmark of all amyloid diseases, a common therapeutic strategy is to develop molecules that inhibit aggregation. However, this approach has yielded limited success. Many amyloid proteins directly interact with lipid membranes. These interactions promote distinct aggregation pathways and often result in membrane damage leading to toxicity. As a result, directly targeting the ability of amyloids to bind lipid membranes represents a novel therapeutic strategy. As a proof of principle, the interaction between lipid membranes and mutant huntingtin protein (htt) aggregates was used to test this strategy. Mutant htt containing an expanded polygulatmine (polyQ) domain …

Exogenous Factors That Impact Huntingtin Aggregation, Adam Skeens

Graduate Theses, Dissertations, and Problem Reports (ETD)

While expansion of a polyglutamine (polyQ) domain is the immediate cause of huntingtin (htt) aggregation associated with Huntington’s Disease (HD), other cellular factors modify aggregation. These include interactions with cellular membranes, protein biding partners, molecular crowding, and proteinaceous seeds. Here, two important factors are biophysically characterized: 1) the interaction of htt with endomembranes and 2) proteinaceous seeds obtained from a variety of htt-derived peptides. In the first project, the aggregation of htt at bilayer interfaces and in the presence of divalent cations was investigated. A major cellular factor implicated in altered htt aggregation is the binding of lipids. Furthermore, the …

Cell Signaling And Stress Response In The Yeast Saccharomyces Cerevisiae: A Study Of Snf1, Scott E. Arbet Ii

Graduate Theses, Dissertations, and Problem Reports (ETD)

Saccharomyces cerevisiae are yeast that are unicellular eukaryotic organisms that are well studied as a model organism for understanding fundamental cellular processes. The ability of yeast to sense nutrient availability is crucial for their survival, growth, and reproduction. Yeast cells use various mechanisms to sense and respond to nutrient availability, including transporter-mediated uptake, receptor-mediated signaling, and sensing of metabolites. The subcellular localization of nutrient-sensing components is crucial for yeast function in nutrient sensing and signaling. Protein complexes, such as the AMP-activated protein kinase (AMPK) pathway, in nutrient sensing and response, as well as the downstream effects of these pathways …

Specialized Metabolism In Retina, Retinal Pigmented Epithelium, And Testis, Siyan Zhu

Graduate Theses, Dissertations, and Problem Reports (ETD)

The retina and its neighboring retinal pigmented epithelium (RPE) are high energy-demanding and metabolically active tissues with specialized and complementary metabolism. They are metabolically interdependent and impact each other’s viability. Interestingly, many of the metabolic features in the retina and RPE are shared with the testis. For example, testis is also energy costly due to continuous sperm differentiation and it has similar metabolic inter-dependence between different testis cells. Both the retina and testis are vulnerable to mitochondrial metabolic impairments.

We conducted three research projects to understand 1) the nutrient utilization and communication in retina and RPE; 2) The profiling of …

Vinyl Chloride Accident Unleashes A Toxic Legacy, Chengjun Li, Peng Gao, Riqing Yu, Huan Zhong, Mengjie Wu, Su Shiung Lam, Christian Sonne

Biology Faculty Publications and Presentations

A railroad accident on February 3, 2023, led to the release and combustion of 115,580 gallons, equivalent to over 437,000 L, of vinyl chloride monomer (VCM) in East Palestine, Ohio [1]. This monomer is used in polyvinyl chloride (PVC) production, and its burning produces additional toxins such as hydrochloric acid and lethal phosgene, known as a notorious chemical weapon during World War I

Of Transcription Factor And Transformation: Elucidating Gene Function In The Common Ice Plant, Mesembryanthemum Crystallinum, Chinenye Lilian Izuegbunam

Dissertations and Theses

Abiotic stresses negatively affect plant growth and development across the globe, which also affect the production of food, feed, biofuel, and fiber to meet the demands of a growing population. Thus, developing novel strategies to increase abiotic stress tolerance in crops is necessary. One of these strategies is exploring transcription factors (TFs) in Crassulacean Acid Metabolism (CAM) plants to improve plant abiotic stress tolerances. Therefore, the first objective of this dissertation determine the abiotic stress tolerance function of a CAM TF, McHB7opt in Arabidopsis. This study found that McHB7opt increased stress-responsive pathways related to seed germination and early seedling development. …

Csi Botany: Dna Barcode “Fingerprints” Identify Cryptic Urban Flora, Luis R. Vega

Theses and Dissertations

As short genomic markers, DNA barcodes can play a role in conservation by identifying cryptic species and hybrids when morphological approaches fall short. Here we present our application of barcodes to the identities of two wetland taxa as part of an ongoing floristic inventory of Van Cortlandt Park (VCP), Bronx, NY. Previous barcode data by Marriott et al. (2018) identified the VCP lake water lily as the exotic Nymphaea alba, rather than the native N. odorata as historically described. In addition, cattails in the park were historically identified as the native Typha latifolia and the exotic T. angustifolia …

Nitrogen Isotopes In Deep Sea Corals; A Potential Tracer Of Paleoceanographic Conditions, Sylvia Bergerud

Scripps Senior Theses

Abstract

In the face of anthropogenic climate change, increasing pressure is being mounted on contextualizing current climate altercations compared to those of the past. One key tracer of climate variation is the isotopic ratio of 15N compared to 14N, which tracks biological and chemical reactions throughout the N cycle. However, it is difficult to find accurate palaeoceanographic records of N isotope fractionation, as most sedimentary and organic samples are subject to extensive diagenesis, degradation, and erosive processes. Scleractinian corals present a potential solution to this lack of accurate data. Multiple studies indicate that, due to their protective aragonite skeletons and …

Comparison Of Bone Robustness Between Fore- And Hindlimb In Neonatal And Infant Galago, Jeremy Busken

Williams Honors College, Honors Research Projects

According to Wolff’s law, bone is constantly subject to change based on loading patterns (Ruff et al., 2006). Those subjected to greater stress become more robust by increasing bone mineral density and often changing geometric properties. Previous studies of primate anatomy have found significant differences in bone robustness between the fore- and hindlimbs in adult leaping primates. Because leaping primates, such as Galago senegalensis and Galago moholi, subject their hindlimbs to much greater stress, this difference in robustness may come as a result of bone functional adaptation/Wolff’s law. This study sought to investigate this possibility by testing neonatal and infant …

Mammalian Dihydropyrimidine Dehydrogenase: Employing Transient State Kinetic Methods To Determine Catalytic And Inhibitory Mechanisms, Dariush Forouzesh

Dissertations

Dihydropyrimidine dehydrogenase (DPD) catalyzes the two-electron reduction of pyrimidine bases uracil and thymine as the first step in pyrimidine catabolism. The enzyme achieves this simple chemistry using a complex cofactor set including two flavins and four Fe4S4 centers. The flavins, FAD and FMN, interact with respective NADPH and pyrimidine substrates and the iron-sulfur centers form an electron transfer wire that links the two active sites that are separated by 56 Å. DPD accepts the common antineoplastic agent 5-fluorouracil (5FU) as a substrate and so undermines the establishment of efficacious toxicity. Though studied for multiple decades, a precise description of the …

The Affect Of Dha Concentration On Lipid Membrane Fluidity, Elise Rezabeck

Williams Honors College, Honors Research Projects

My proposed project will be creating large unilaminar vesicles with varying concentrations of DHA in the vesicles. The diffusion in and out of these vesicles will be tracked by using singular lipid molecules. These singular lipid molecules will be tagged with fluorescence and viewed using an internal reflection fluorescence microscope. The data collected over the course of this project will then be analyzed using Matlab. The result of the project will be to find the specific lipid diffusion constant of these unilaminar vesicles. The relationship between the concentration of DHA and lipid diffusion and membrane fluidity will be found as …

Dual Mechanisms Contributing To Pyruvate Dehydrogenase Activity Deficiency In A Barth Syndrome Cell Model, Zhuqing Liang

Wayne State University Dissertations

Barth syndrome (BTHS) is a rare genetic disease that results from mutations in the TAFAZZIN gene, which encodes the cardiolipin (CL) remodeling enzyme tafazzin (Taz). The mechanisms linking perturbation of CL remodeling and the pathological features of BTHS are not understood. We have recently reported that intermediary metabolism is perturbed in BTHS, and activity of the metabolic gatekeeper enzyme pyruvate dehydrogenase (PDH) is deficient in BTHS models. The mechanism whereby PDH is regulated by Taz is unknown, and this knowledge gap represents an obstacle to the development of therapeutics to treat BTHS. Using an established C2C12 myoblast model of BTHS, …

Biological Adaptations Leading To Metastatic Potential In Ovarian Cancer, Hussein Chehade

Wayne State University Dissertations

Ovarian cancer induces most deaths from gynecological cancers. Patients succumb due to heavy metastatic tumor burden, which accounts for 90% of cancer related deaths and is characterized by the dissemination of malignant cells from primary tumor to secondary site(s), partaking in cancer progression. Ovarian cancer progression is an extremely demanding process that requires cancer cells to be able to survive anoikis conditions and be metabolically flexible to survive microenvironmental changes during transit to a secondary site. Mitochondrial Nuclear Retrograde Regulator 1 (MNRR1) is a bi-organellar protein primarily present in the mitochondria by which it can prevent apoptosis and/or enhance mitochondrial …

From Culture To Metagenomics: A Comprehensive Evaluation Of The Female Reproductive Tract Microbiome In Pregnancy, Jonathan Panzer

Wayne State University Dissertations

The advent of Next Generation Sequencing technologies prompted novel investigations of the microbiome. These revealed both increased diversity of known microbiomes such as those of the gut, oral cavity and vagina, but also bacterial DNA in tissues previously considered sterile such as the blood, liver, brain, and placenta. Thus, previous paradigms of sterility, based primarily on culture data, were called into question. However, interpretation of bacterial DNA signals from low-microbial biomass tissues is complex due to the strong potential for contamination and interference from the surrounding environment. Yet, many new methodologies are being developed to help isolate valid bacterial DNA …

Plant Cell Wall Composition And In Vitro Fermentation Characteristics Of Cool-Season Forage Grasses From Two Growing Seasons In Central Kentucky, Sophia Danielle Newhuis

Theses and Dissertations--Animal and Food Sciences

Grass cell walls are rich in cellulose, hemicellulosic arabinoxylan (AX) polysaccharides, and lignin. AX structural differences such as degree and pattern of branching and the ester-linked phenolic acid content could affect plants’ digestibility when used as forage for livestock. However, there is little information about how these structural elements change over the growing season in the vegetative tissue of cool-season perennial grasses. Enhanced information about the cell wall composition and carbohydrate structure of forage material will provide a foundation for expanding our knowledge of how forage cell wall carbohydrate structures are utilized by ruminants. The objectives of this study were …

Characterizing Vhh Domains As Stabilization And Oligomeric Control Modules, Niyati Patel

Graduate Research Theses & Dissertations

The biophysical properties of the VHH domain from heavy-chain-only antibodies obtained from the Camelidae family has expanded opportunities for novel antibody applications. The small, single domain nature of VHH domains makes them attractive modules for fusion proteins. Here, two VHH fusion systems were evaluated, RNase A-anti-RNase A VHH and GFPMut3aR80Q-anti-GFP VHH, to investigate how antigen-VHH fusions may enhance protein thermostability. The introduction of various length flexible linkers was hypothesized to play a role in stability, as well as influence the oligomeric state. Bovine Pancreatic Ribonuclease A, or RNase A, is an enzyme belonging to the ribonuclease A superfamily, which is …

Role Of Micrornas In Intestinal Inflammation And Barrier Homeostasis After Alcohol And Burn Injury, Caroline J. Herrnreiter

Dissertations

MicroRNAs are small noncoding RNA molecules that negatively regulate gene expression. Within the intestinal epithelium, miRNAs play a critical role in gut homeostasis and aberrant miRNA expression has been implicated in various disorders associated with intestinal inflammation and barrier disruption. In this study, we sought to profile changes in intestinal epithelial cell miRNA expression after alcohol and burn injury and elucidate their impact on inflammation and barrier integrity. In a more targeted approach, we began by focusing on anti-inflammatory miRNAs that, when downregulated, could exacerbate inflammation and result in intestinal barrier disruption. Using a mouse model of acute ethanol intoxication …

Effects Of Nicotine Vs Non-Nicotine E-Cigarettes On The Aggression Behavior Of Crayfish, Alex Kimble

Williams Honors College, Honors Research Projects

This study looks at the effects of e-cigarette vapor with and without nicotine on the aggression behavior of crayfish (Procambarus clarkii). The treatment groups were control, nicotine, and non-nicotine. The mass, sex, and condition of their appendages were recorded before random assignment. For the purpose of this study only male crayfish were used as there were not enough female crayfish. The crayfish were then randomly assigned to each group and contained ten crayfish that were subjected to the e-cigarette vapor infused water environment for a twenty-four hour period. The control group did not contain e-cigarette vapor and was exposed to …

Effect Of An Oncogenic Her2 Mutant On Egfr Activity, Paige Kalik

Williams Honors College, Honors Research Projects

Studies have shown that HERs are involved in the progression of human cancers. Researchers have found that HER2 mutations in colorectal cancer are similar to mutations found in breast cancer. Recombinant antibodies are effective therapeutic treatments for cancers. Antibodies can also be used to determine how proteins function under normal and pathophysiological conditions while also identifying interacting partners. In this Honors Project, my aim is to investigate the effect of an oncogenic mutant of HER2. Considering the information above, the question researched in this project was: how does the S310F mutation affect the organization and function of HER2? The specific …

A Characterization Of Key Residues In Class I Viral Fusion Proteins Important For Fusogenic Activity, Hadley E. Neal

Theses and Dissertations--Molecular and Cellular Biochemistry

Viral fusion proteins are critical for viral entry and subsequent infection. Class I fusion proteins are characterized by synthesis as an inactive precursor requiring cleavage by a host cell protease to become fusion competent. Though vaccine and antiviral therapeutic developments often target the fusion protein, questions surrounding cleavage dynamics and protein stability remain. The work presented in this dissertation investigates specific regions of three class I viral fusion proteins in an effort to identify key residues involved in proteolytic processing and membrane fusion.

The trimeric severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) spike protein (S) mediates receptor binding, facilitates fusion …

Characterization Of The Function And Regulation Of The Hmpv Phosphoprotein, Rachel Thompson

Theses and Dissertations--Molecular and Cellular Biochemistry

Human metapneumovirus (HMPV) is a non-segmented, negative strand RNA virus (NNSV) that frequently causes respiratory tract infections in infants, the elderly, and the immunocompromised. Despite the initial identification of HMPV in 2001, there are currently no FDA approved antivirals or vaccines available. Therefore, understanding the mechanism of HMPV replication is critical for the identification of novel therapeutic targets. A key feature in the replication cycle of HMPV and other NNSVs is the formation of membrane-less, liquid-like replication and transcription centers in the cytosol termed inclusion bodies (IBs). Recent work on NNSV IBs suggests they display characteristics of biomolecular condensates formed …

The Role Of Chromatin Structure In Circular Rna Biogenesis, Function And Disease, Rebekah Eleazer

Theses and Dissertations--Molecular and Cellular Biochemistry

Fundamental to cellular differentiation, development, and physiology is the precise regulation of gene expression. At the center of this control lies chromatin, and disruptions in chromatin biology are key contributors to complex human diseases. By convention, gene expression analysis primarily focuses on transcript abundance, however the splicing of transcripts into distinct isoforms is also of biological relevance. One new form of alternative splicing, backsplicing, is responsible for generating circular RNAs (circRNAs), which are emerging as essential components to gene regulatory networks. However, unlike other forms of alternative splicing, the role that chromatin plays in backsplicing and circRNA formation remains poorly …

Investigating The Roles Of Platelet Bioenergetics In Hemostasis And Thrombosis, Kanakanagavalli Shravani Prakhya

Theses and Dissertations--Molecular and Cellular Biochemistry

Platelets use a series of energy-dependent processes to mediate hemostasis, yet it is unclear which metabolic fuels/pathways are critical for platelet function. Platelets are metabolically flexible, switching between glycolysis and oxidative phosphorylation (OxPhos) depending on oxygen tension and substrate availability. The deletion of GLUT1 and GLUT3 together revealed an essential role in platelet function and hemostasis. To study platelet bioenergetics, we used clot contraction. We created a sensitive and inexpensive method to simultaneously assess clot contraction kinetics to directly compare and define the effects of different treatments or genetic manipulations on platelet function.

Since the pharmacological inhibitors cannot be used …

The Role Of Dynamin Related Protein 1-Mediated Mitochondrial Dynamics In Colorectal Cancer, Sumati Raj Hasani

Theses and Dissertations--Molecular and Cellular Biochemistry

Cancer cells are known for their ability to adapt variable metabolic programs depending on the availability of specific nutrients. Consequently, metabolic reprogramming has been increasingly recognized as a major mechanism that fuels tumorigenesis and disease progression. Here, we have investigated the role of a pro-fission factor, Dynamin-Related Protein 1 (Drp1), in promoting metabolic adaptation in colon cancer.

Our studies have shown that fatty acid (FAs) uptake alters cellular metabolic pathways in colon cancer cells to favor fatty acid oxidation through the activation of Drp1. Uptake of FAs induces mitochondrial fragmentation by promoting ERK-dependent phosphorylation of Drp1 at the S616 site, …

The Development And Characterization Of Nanobodies Specific To Protein Tyrosine Phosphatase 4a3 (Ptp4a3/Prl-3) To Dissect And Target Its Role In Cancer., Caroline Smith

Theses and Dissertations--Molecular and Cellular Biochemistry

Protein Tyrosine Phosphatase 4A3 (PTP4A3 or PRL-3) is an oncogenic dual-specificity phosphatase that drives tumor metastasis, promotes cancer cell survival, and is correlated with poor patient prognosis in a variety of solid tumors and leukemias. The mechanisms that drive PRL-3’s oncogenic functions are not well understood, in part due to a lack of research tools available to study this protein. The development of such tools has proven difficult, as the PRL family is ~80% homologous and the PRL catalytic binding pocket is shallow and hydrophobic. Currently available small molecules do not exhibit binding specificity for PRL-3 over PRL family members, …